Input Synchronization for Cyclic Queueing and Forwarding (CQF)

Abstract

According to embodiments, a first device transmits a timing marker frame (TMF) in a first transmission cycle. The first device determines a transmission time of the TMF. The first device determines a time difference between the transmission time of the TMF and a start time of a second transmission cycle. The first device transmits to a second device a phase offset message (POM) indicating the time difference. The first device transmits frames in a transmission cycle subsequent to the first transmission cycle.

What is claimed is: 
     
         1 . A method comprising:
 transmitting, by a first device to a second device, a timing marker frame (TMF) in a first transmission cycle;   determining, by the first device, a transmission time of the TMF;   determining, by the first device, a time difference between the transmission time of the TMF and a start time of a second transmission cycle;   transmitting, by the first device to the second device, a phase offset message (POM) indicating the time difference; and   transmitting, by the first device to the second device, frames in a transmission cycle subsequent to the first transmission cycle.   
     
     
         2 . The method of  claim 1 , wherein the TMF indicates a TMF identifier (TMFID) that uniquely identifies the TMF, and wherein the POM indicates the TMFID. 
     
     
         3 . The method of  claim 1 , wherein the transmission time of the TMF is a local time at which a first bit of the TMF is transmitted from a hardware of the first device. 
     
     
         4 . The method of  claim 1 , the time difference is the transmission time of the TMF minus the start time of the second transmission cycle. 
     
     
         5 . The method of  claim 1 , wherein the second transmission cycle is the same as the first transmission cycle, or wherein the second transmission cycle is after the first transmission cycle, or wherein the second transmission cycle is before the first transmission cycle. 
     
     
         6 . The method of  claim 1 , wherein a transmission cycle length on the first device and a receive cycle length on the second device are the same. 
     
     
         7 . The method of  claim 1 , wherein all the frames transmitted by the first device in a transmission cycle subsequent to the first transmission cycle are received by the second device in a same receive cycle without time synchronization between the first device and the second device. 
     
     
         8 . The method of  claim 1 , wherein the TMF is not a first frame in time in the first transmission cycle transmitted by the first device. 
     
     
         9 . The method of  claim 1 , wherein the first device transmits M TMFs in N transmission cycles, and wherein M is less than N. 
     
     
         10 . A method comprising:
 receiving, by a second device from a first device, a timing marker frame (TMF) in a first receive cycle;   receiving, by the second device from the first device, a phase offset message (POM) indicating a time difference;   determining, by the second device, a receive time of the TMF;   determining, by the second device, a start time of a second receive cycle based on the receive time of the TMF and the time difference indicated in the POM; and   receiving, by the second device from the first device, frames in a receive cycle subsequent to the first receive cycle based on the start time of the second receive cycle.   
     
     
         11 . The method of  claim 10 , wherein the TMF indicates a TMF identifier (TMFID) that uniquely identifies the TMF, and wherein the POM indicates the TMFID. 
     
     
         12 . The method of  claim 10 , wherein the receive time of the TMF is a local time at which a first bit of the TMF is received by a hardware of the second device. 
     
     
         13 . The method of  claim 10 , the time difference is the receive time of the TMF minus the start time of the second receive cycle. 
     
     
         14 . The method of  claim 10 , wherein the second receive cycle is the same as the first receive cycle, or wherein the second receive cycle is after the first receive cycle, or wherein the second receive cycle is before the first receive cycle. 
     
     
         15 . The method of  claim 10 , wherein a transmission cycle length on the first device and a receive cycle length on the second device are the same. 
     
     
         16 . The method of  claim 10 , wherein all the frames transmitted by the first device in a transmission cycle subsequent to transmission of the TMF are received by the second device in a same receive cycle without time synchronization between the first device and the second device. 
     
     
         17 . The method of  claim 10 , wherein the TMF is not a first frame in time in the first receive cycle received by the second device. 
     
     
         18 . The method of  claim 10 , wherein the second device receives M TMFs in N receive cycles, and wherein M is less than N. 
     
     
         19 . A first device comprising:
 a non-transitory memory storage storing instructions; and   one or more processors in communication with the non-transitory memory storage, wherein the instructions, when executed by the one or more processors, cause the first device to perform operations including:   transmitting, to a second device, a timing marker frame (TMF) in a first transmission cycle;   determining a transmission time of the TMF;   determining a time difference between the transmission time of the TMF and a start time of a second transmission cycle;   transmitting, to the second device, a phase offset message (POM) indicating the time difference; and   transmitting, to the second device, frames in a transmission cycle subsequent to the first transmission cycle.   
     
     
         20 . A second device comprising:
 a non-transitory memory storage comprising instructions; and   one or more processors in communication with the non-transitory memory storage, wherein the instructions, when executed by the one or more processors, cause the second device to perform operations including:   receiving, from a first device, a timing marker frame (TMF) in a first receive cycle;   receiving, from the first device, a phase offset message (POM) indicating a time difference;   determining a receive time of the TMF;   determining a start time of a second receive cycle based on the receive time of the TMF and the time difference indicated in the POM; and   receiving, from the first device, frames in a receive cycle subsequent to the first receive cycle based on the start time of the second receive cycle.